The invention is directed to a method for acquiring network knowledge in the individual transmission-associated operating locations of a digital transmission network comprising a plurality of network nodes, whereby an auxiliary information is mixed into the overhead of digital signals for the transmission of said digital signals.
European Patent Application EP 0 048 853 A1, German Published Application DE-OS 24 41 099 and the Proceedings IEEE, Vol. 2, 9.6.1987, International Conference on Communications, 7-10.06.1987, Seattle, Wash. respectively disclosed telephone switching networks having switching centers via which subscribers are connected.
In transmission systems of digital technology, it is prior art that various digital signal connections DSV are further through-connected in the network nodes either as a whole or separated into individual digital signal connections DSV. Distributors wherein these digital signal connections DSV are allocated to the respective equipment corresponding to the desired connection management and, thus, wherein these connections are through-connected are arranged preceding and following every equipment of a hierarchy level.
It is also prior art that these distributors are computer-controlled and are functionally executed as coordination switches. It is likewise known within the course of a computer-controlled digital signal connections DSV that the various multiplexers and the appertaining distributors are combined to form a combined equipment. The distributors and the corresponding multiplexing stages can thus be driven and administered via a central computer. Given faults occurring in the transmission system, this central controller enables a standby circuit as would otherwise be implemented on site with operating personnel. The disadvantage of the prior art is that, given an outage of the central computer, the original path information of a digital signal group can no longer be reconstructed within the network node since all of the information about the line management is situated in the central computer.
The external servicing and display arrangements or, respectively, sub-computers situated in the individual network nodes are not in the position to restore the original or the momentary path of the connection.
European Patent Application EP 0 214 398 A1 discloses a method for monitoring and controlling the traffic in digital transmission networks having network nodes via a control network. Every digital signal thereby contains an identifier that covers information about the traffic conditions of the individual digital connections such as, for example, a continuous numbering of all sources having directional indication or indication of locality or area. The identifier of a desired digital signal connection is communicated via the control network to the appertaining network nodes that are correspondingly controlled. The identifier of the digital signals is also monitored therein. It in fact contains an information about the connection but not about the path, so that a connection can no longer be set up given the absence of path information via the control network.